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Advanced d20 Magic » Invocation, dynamic spellcasting
When casting a spell, one thing you can do is declare the name of the spell as part of the process, thus adding additional mental force to channelling the power for the spell. This adds no time to the spellcasting — it still requires only a standard action — but it does make it clear to any nearby opponents what the character intends to cast. Invocation requires no gestures and may be used even if the spellcaster is tied up or otherwise unable to move, as long as he or she is still able to speak. When using Invocation, the character simply shouts the name of his or her spell as part of casting. Doing so alerts everyone who can hear the character as to what spell is being cast. Invocation grants the spellcaster a +5 bonus to the Fortitude Save to resist Spell Drain and the Control check (if necessary)
